1. Field of the Invention
The present invention relates to a charge transfer device and, more particularly, to a charge transfer device comprising one or a plurality of first charge transfer path(s) to transfer the charges in a first predetermined direction and a second charge transfer path to transfer the charge transferred through the first charge transfer path(s) in a direction which is substantially perpendicular to the first transferring direction of the charges by way of the first charge transfer path(s).
2. Description of the Prior Art
The charge transfer device as mentioned above can be implemented, for example, in a combination of the vertical transfer register and horizontal transfer register in an interline type CCD solid-state image sensing device, or in a combination of a storage part consisting of a vertical transfer register and a horizontal transfer register for reading out in a frame transfer type CCD solid-state image sensing device, or in a combination of the horizontal transfer register and vertical transfer register in a line address type CCD solid-state image sensing device.
On the other hand, in such conventional solid-state image sensing devices, the connecting portion of the horizontal (or vertical) transfer register and the vertical (or horizontal) transfer register has a construction as shown, for example, in FIG. 1. Namely, in the diagram, RH denotes a horizontal (or vertical) transfer register and RV indicates a vertical (or horizontal) transfer register. As shown in the diagram, the transfer register RH crosses the transfer register RV at substantially right angles, and the length of one transfer cell RV.sub.b in the transfer register RV at the junction with the transfer register RH is equal to the width of the transfer register RH. In addition, arrows H and V in the diagram represent the transferring directions of the charges in registers RH and RV, respectively, and RH.sub.a and RV.sub.a each indicate one transfer cell,
In order to prevent deterioration in transfer efficiency even when the charges are transferred at a high speed, assuming that the capacity of each transfer cell of the transfer registers is constant, it is known that the length in the transferring direction of the charges should preferably be as short as possible. On the other hand, in the construction shown in FIG. 1, the length of the transfer cell RV.sub.b of the transfer register RV at the junction is long in the charge transfer directions of both the transfer registers RH and RV. Therefore, particularly upon transfer of the charges at a high speed, the transfer efficiency of the charges at this junction (RV.sub.a) becomes worse, so that good high-speed transfer of charges can be hardly expected.